1. Field of the Invention
The present invention relates to an image display device using a semiconductor laser for a light source, and particularly relates to an image display device built into various electronic apparatuses.
2. Description of the Related Art
In recent years, a technique of using a semiconductor laser for a light source of an image display device has drawn attention. Compared to a mercury lamp that has been widely used in the image display device in the related art, the semiconductor laser has a variety of advantages such as the points that the laser shows an excellent color reproducibility, can be lit instantly, has a long life, can reduce power consumption through high efficiency, and can be easily miniaturized, for example.
These advantages of the image display device using the semiconductor laser are achieved significantly when the image display device is built into portable electronic apparatuses. For example, a technique of installing the image display device using the semiconductor laser into a mobile phone terminal is known (JP 2007-316393 A). In this way, when the image display device is built into portable electronic apparatuses, it is possible to display images on a screen while enlarging the images as necessary, and convenience can be improved accordingly.
The image display device using the semiconductor laser for the light source can also improve the convenience even when the apparatus is built into a portable information processing apparatus (commonly known as a laptop). In this case, the image display device is accommodated inside a case of a main body portion where a keyboard is disposed.
Incidentally, the case of the portable information processing apparatus is formed to be flat for the purpose of improving portability. Therefore, it causes problems in that a portion of the image displayed on the screen is missing or the image is slanted.
For instance, the case of the portable information processing apparatus is formed to be flat for the purpose of improving portability. Accordingly, when the portable information processing apparatus is placed on a desk, the image display device comes close to the surface where the image display device is placed, and thus a laser beam emitted from the image display device is blocked by the surface. In this state, the bottom portion of the image displayed on the screen is missing, whereby a problem that the image cannot be displayed properly occurs.
The image display device is provided such that the accommodation space thereof is opened in the lateral surface of the case of the portable information processing apparatus and the emission window of the image display device is placed in the lateral surface of the case of the portable information processing apparatus. Herein, the case of the portable information processing apparatus accommodates a frame supporting the keyboard and an internal control board. Since the frame is disposed along the upper surface of the case where the keyboard is arranged, the accommodation space for the image display device is also made to be formed along the upper surface of the case. In addition, in some of the portable information processing apparatuses, the upper surface of the case where the keyboard is arranged is made to be slanted so that the side that is near to a user is lowered when the portable information processing apparatus is placed on the desk. In this configuration, the accommodation space for the image display device is also formed to be slanted along the upper surface of the case. However, since the case of the portable information processing apparatus is formed to be flat to improve the portability, there is not enough room for the accommodation space for the image display device. Also, since it is not easy to provide the image display device to be parallel to the desk surface where the portable information processing apparatus is placed, it is inevitable that the image display device is provided to be slanted with respect to the surface. As a result, the image is displayed on the screen while being slanted, so that a problem occurs in that the image cannot be displayed properly on the screen.